Human activity recognition has been a popular research topic in ubiquitous computing for its important role in human daily life. HAR attempts to identify and analyze human activities using learned high-level knowledge from raw data of various types of sensors. Several surveys have summarized recent progress in HAR. [1]}, [2]} summed up vision-based HAR and [3]}, [4]} summarized recent work from a different point. In this paper, we focus on work about sensor-based HAR.
